Effects of paraasite larva excretory-secretory products on hemocytes of intermediatehost snail

采用21种异硫氰酸荧光素偶联凝集素（Con A、DBA、PNA、RCA120、SBA、UEA-I、WGA、GSL-I、LCA、PHA-E、PHA-L、PSA、SJA、S-WGA、GSL-II、DSL、ECL、Jacalin、LEL、STL、VVL）表征中间蜗牛寄主（Biomphalaria glabrata）血细胞的表面碳水化合物。两种血细胞类型，粒细胞和透明细胞被描述从光斑弓形虫血液，粒细胞是最直接参与破坏寄生虫的细胞。凝集素抑制α -甲基甘露糖苷结合到两种血细胞类型，凝集素抑制n -乙酰- d -葡萄糖胺结合到透明质细胞。附生棘孔虫感染后，凝集素结合模式没有改变。用流式细胞术对蜗牛宿主血细胞进行分析。使用Caulter EPICS Profile流式细胞仪进行前向和侧向散射测量。新鲜抽取的血细胞的大小分布是单峰和连续的，没有离散的亚群，并且不受年龄或感染副链球菌的影响。然而，随着螺体大小的增加和对生依蚊感染的增加，血细胞的侧散性被破坏。采用dna特异性碘化丙啶荧光法测定细胞周期各阶段的血细胞比例。感染钉螺中DNA含量较低的血细胞比例增加。

Twenty-one fluorescein isothiocyanate-conjugated lectins (Con A,DBA,PNA,RCA120, SBA,UEA-I,WGA,GSL-I,LCA,PHA-E,PHA-L,PSA,SJA,S-WGA,GSL-II,DSL,ECL,Jacalin, LEL,STL,VVL) were used to characterize surface carbohydrates of intermediate snail host (Biomphalaria glabrata) hemocytes. Two haemocyte types, granulocytes and hyalinocyte was described from B.glabrata blood, and granulocytes are the cell most derectory involoved in destruction of parasites. Lectins inhibitable alpha-methylmannoside bound to both hemocyte types, and lectins inhibitable N-acetyl-_D-glucosamine bound to hyalinocytes. There was no change in lectin-binding patterns by infection with Echionostoma paraensei.Flow cytometric analysis was performed on hemocytes of snail host. Forward and side scatter measurements were made using a Caulter EPICS Profile flow cytometer. The size distribution of freshly drawn hemocytes was unimodal and continuous, with no discrete subpopulations, and is not affected by age or by infection with E.paraensei. However, the side scatter of hemocytes was decteased with increasing of snail size and infection with E.paraensei. The proportion of hemocytes in each stage of cell cycle was measured using DNA-specific propidium iodide fluorescence. The proportion of hemocytes with lower DNA content increased in infected snails.